Recent evidence suggests that club drugs, such as lysergic acid diethylamide (LSD), methylene-dioxy-methamphetamine (MDMA or Ecstasy), gamma-hydroxybutyrate (GHB), Ketamine, Rohypnol, methamphetamine, and psilocybin, are gaining in popularity, users are getting younger, and serious consequences can result from using these substances. These factors have caused alarm among many in the public health, law enforcement, and policy-making communities. Much of this concern stems from the fact that we know very little about the factors that affect club drug trends, the people who use these substances, and the exact method in which they are used. The proposed study involves interviewing a sample of 250 juvenile offenders in Lane County (Eugene), Oregon, that is racially/ethnically diverse, includes both genders, and reports high rates of club drug use. Additionally, a sample 30 juveniles who have extensive experience with club drugs and the rave scene will be administered a detailed, qualitative interview. The proposed investigation will (1) determine whether users of various club drugs are "different" from non-club drug users or users of other drugs in terms of demographic characteristics, life experiences, etc.; (2) identify how, where, and from whom youth learn about and obtain various club drugs and how much they spend on them; (3) ascertain where, when, how, and in what social contexts youth use club drugs and what substances they mix with them; (4) document youth attitudes and beliefs about various club drugs and reasons why they use them; and (5) determine whether youth have experienced or witnessed any consequences of using various club drugs. Simple descriptive analyses, as well as multivariate binomial logistic, multinomial logistic, mixed-effects ordinal regression, latent class, and attributable risk models, will be employed to achieve the specific aims outlined above. An effort will be made to test several etiological models of club drug use, identify risk and protective factors, and understand the subculture that embraces these substances. This information will help inform subsequent research on club drugs and substance-specific education/prevention and interdiction initiatives.